Concord Grapes Green

Caring for Young Grape Vines

My name is David Handley, I'm with the Universityof Maine Cooperative Extension, and we're here to talk about how to prune and traina young grapevine. This is a vine that was planted last spring. We got it from a dormantplant, or rooted cutting, and you can see the original part of the planting right here.This is what we got from the nursery, with a good root system under it. We planted it,and we had a bud break and some vine growth. This is last year's growth right here. Thiswas a green shoot. Typically, you may get more than one shoot developing. You may haveseveral buds on here. We want to prune this back to one strong vine, your strongest one.We're going to arrange for that to be tied

up to a trellis, because this particular vineis what's going to become our permanent trunk, or the permanent part of the plant that'sgoing to be with us for the life of the planting. We want to make sure it's the strongest ofthe vines that we can choose from. Any other one that developed that's very weak, we canjust cut that out, select our best one. The time of year to make these cuts are whenthe canes are dormant, and this is going to be really any time after the new year, untilthey bud out in late March, early April. We hope in the first year that we get enoughgood growth that we can tie it to the lower trellis wire.Typically here in Maine, we're going to be

pruning to either a four arm kniffin trainingsystem, or an umbrella kniffin training system. Those trellises consist of two wires, oneset at about two and a half feet, and a second wire set at about five feet.We hope in the first year that we're going to get enough good growth to reach at leastthe bottom wire, but in order to make sure it's growing straight, you can see we supportedthis with a small bamboo pole. Any kind of planting stake will work, and we just tiethat vine up as it grows, rather than let it grow along the ground where it can getrot problems, and not develop a nice straight growth like we want. We tie it up, just likeyou'd tie up a beef steak tomato, get the

growth that you want.As I said, we've got pretty good buds here, reaching up to the first wire. You can seethat I actually make it to the top wire, but you can see the growth up here is very scrawnyand spindly, and isn't really going to lead to a good, strong trunk. I'd rather actuallystart new growth for reaching to this top wire for next year.What that means is that I'm actually going to cut this off here, rather low, to try toget this bud here to break and give me a much stronger shoot to develop my trunk to thetop wire next year. I can just take that there, and then, instead of using the bamboo polethis year, I can just tie it to the wire.

This bud will hopefully break, and give mea good, strong shoot, that I'm going to reach the second wire next year. Of course, thesebuds lower down will also break, and if this one happens to be weak, I may select one ofthese. But, if this bud does turn out to be a strong shoot, I'll be cutting these offnext winter and getting my single trunk back up to the top wire.Next year, when this does reach the top wire, eventually what we'll be doing is taking oneyear old cane, and either draping it over this top wire and connecting it to the bottomwire in an umbrella kniffin, or we'll be taking one cane at the top wire on each side, andone cane at the bottom wire on each side,

to create four arms of one year old growth,for a four\uc0\u8209 arm kniffin system. Both systems work pretty well for concretetype grapes here in a cold climate like Maine.

Knowing when to harvest your grapes

gt;gt;TOM VAN DER LINDEN: It's a beautiful Septemberday in Minnesota. We're at the Horticultural Research Center at the University of Minnesotaand it's time to harvest the grapes. But how do you know when it's time to pické I'll showyou how to tell when the grapes are ripe and I'll show you some measurements to be sure,because it's important. After all, better grapes mean better wine. The most important day of the year is theday you pick. It sets in motion the annual harvest and it also determines the kind ofwine you'll make. As a grape grower and a wine maker you should keep a notebook. You'llbe glad to have records in the months and

years to come. Let's start with sight, touch, smell, andtaste. You want your grapes to be rich in color, not green. A ripe grape will crusheasily, but not be shriveled. A ripe grape is plump, and thickly juicy. It's a balancebetween sweet and tart. Each variety develops special flavors that we call varietal flavor.A fully ripe grape develops its varietal flavor more fully. Does the skin have varietal flavoré Is itherbaceous, or is it vegetal, like a green pepperé Is the aftertaste pleasant or is itbitteré Chemical or vinegar tastes or smells are flaws so take good notes if you have thatproblem. One more time, taste the grape and

imagine what the wine will be. Then we'llmove on to some lab work. It's good to use your senses but it's alsoimportant to measure. You need to measure sugar content, pH, and acidity level. Grapesare mostly water and sugar which will ferment to make wine. Brix is a term that the brewingindustry uses to measure the sugar content of grapes. Brix level helps estimate the alcohollevel of your wine. Like temperature, Brix is measured in degrees. Brix is measured witha refractometer, which you can buy at a winemaking supply store or online. Drop some juice onthe test plate, close the cover firmly and look through the viewfinder. You'll see aline where your juice registers on an internal

scale. In this case, the juice registers 24degrees Brix. A somewhat less convenient, but cheaper methodis to buy a simple glass hydrometer which has a builtin scale. Simply pour your juiceinto the cylinder, float your hydrometer and read the Brix level right off the builtinscale. The more sugar in your wine, the higher your hydrometer will float. As your grapesmature, they store more sugar so the Brix level rises. Different wine styles requiredifferent Brix levels. In general, for white wine, 22 Brix is good. We'll keep an eye onour grapes, testing them periodically, and when we reach our Brix goal, then it's timeto pick.

We now know about sugar and how to measureit. Next let's quickly shift to pH and the pH meter. You may remember pH from high schoolscience class. It's a measure of free hydrogen ions. As our grapes ripen and the sugar rises,the pH will rise too. You can buy an inexpensive, portable pH meter. Be sure you buy pH referencesolutions so you can calibrate your meter. Grape juice is full of natural acids, whichlend important qualities to wine. Every time we measure Brix we should also measure acidlevels. In a way they're opposites; as the Brix goes up, the acid levels go down. Youcan buy a simple acid test kit. It takes a little practice and a little care and you'llwant to make good records, but don't worry,

you can do it! So enough with measuring and tasting, let'sgo pick! Are you ready to pické Let's start by pickinga good sample. Yes, you can pick one grape, put it in your refractometer and take a sugarsample, but it won't be very representative of all your grapes. Instead, pick individualgrapes from many clusters. Sample from both sides of the vine, high and low, in sunnyareas and shaded areas, and pick from different parts of each cluster. An ideal sample mightbe 50 grapes. But if you only have a few vines, it'll be okay to take a smaller sample. Makea note about how they felt, how they smelled,

Four Arm Kniffin System for Growing Grapes

David Handley: I'm David Handley, vegetableand small fruit specialist with the University of Maine Cooperative Extension. Today we'regoing to be talking about a simple system for pruning hardy grapes here in Maine. The pruning system I like to use is very simple.It keeps the plant open, so it gets light in the summer time, but it also protects theplant a little bit in the winter. This system works best with concord type or labrusca typegrapes, which are the grapes that tend to grow best in Maine. There's really a couple of systems that willwork well for labrusca type grapes. The first

one I want to talk about is the four arm kniffin,and that's what we're going to prune first. The four arm kniffin consists of a perennialtrunk, which goes from the ground right up to a top wire, which is set at about fivefeet. Coming off of this trunk, we will have four arms, or canes, oneyear old growth.Two on the top wire, running each side of the top wire, and two on a lower wire. Thislower wire should be set at about two and a half feet off the ground. Every year, we're going to come in and pruneit so we continue to have a perennial trunk, but only four one yearold trunks to producethe fruit.

Here is our permanent trunk. You can see here,this is a cane from last year. Two yearold cane, this was our fruiting cane last summer,and you can see the difference. Here's this year's cane, that nice chocolate brown colorand smooth bark, and here we go with the older cane, the two yearold cane. The bark is startingto peel, and has more of a gray look to it, so we know that this particular shoot isn'tgoing to fruit again. It's the one yearold shoots that come off it that will fruit. This is going to get pruned out, so that wecan keep our fruiting wood closer to the trunk. We'll just take that back to a good fruitingshoot, and we'll start to cut it out. This

is where it gets fun. We need to wrestle thisout of the trellis, and of course, all these little tendrils have tied it up and aroundmost of the growth that's there. It takes a little bit of cutting, but be careful notto break the fruiting canes that you want to leave behind. Pull it off, and that will open the plantingup so we can see what we have left for good fruiting wood for this year. We've taken offthe four fruiting canes that we left last year, and you can see pretty much all that'sleft, at this point, is the green shoots from last year, that will provide us with goodfruit for this year.

Now we need to choose which four we want toput up. We're going to have four canes. One, two, three, four. Two for the lower wire,two for the upper wire, each heading off in different directions. What I want to look for in this case is canethat's got this nice chocolate brown color, and is about 38 of an inch in diameter. Aboutthe width of your little finger. If it's thinner than that, if it's very weak, it won't producegood fruit. Thin stuff like this, less than 38 of an inch in diameter, we'll just cutthat right out. Here we've got one that's going to go in thisdirection, that looks very nice. I'm going

to count, remember we want about 10 buds onit, so we'll count our buds. One, two, three, four, five, six, seven, eight, nine, 10. ThenI just cut out beyond that, because the weaker stuff at the very end isn't going to producevery good fruit. I have my four arms, but you can see I stillhave some leftover canes. What I'm going to use these for are what we call quot;renewal spurs.quot;I'm going to cut these back so that they just have one or two buds on them. What I'm goingto use these buds for, the green shoots that will emerge from these buds and grow out,will be the canes that I'll be putting on the wire next year for fruiting. We call thesequot;renewal spurs.quot;

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